My "white whale" machine was the Laser 128. A friend had one and I enjoyed using it. He'd bring it over to my house and hook it up to the TV. Having a portable computer in the late 80s, even if it wasn't battery powered and didn't have a screen, was pretty cool. I wish I'd bought it from him when he moved to PCs and sold it but at the time I didn't realize it was a good find. It's a bit like the IIc but, I'd argue, is overall a better machine.
I started using the Apple IIe when I was 8 y/o. I started with playing games and programming in Applesoft BASIC, and eventually got to the point of doing rudimentary 6502 assembler programming (mainly modifying programs from magazines). I left the platform at 12 y/o when my father bought a PC.
When I was 14 y/o I scored a copy of the venerable "Inside the Apple IIe" cheap. I spent part of summer vacation really digging-in to the machine. I didn't have a IIe at home so I spent a lot of that summer in the public library using the old IIe machines. They were long-in-the-tooth at that point and no other patrons used them anymore. I got as much time as I wanted on them because of that. It was a fun contrast to the 1 hour / day limit each person got back when I started using them. I could come in when the library opened and spend all day there grinding away.
I feel fortunate having come back to the platform with a broader exposure to programming and while I still had the energy and exuberance of a teenager. I understood a lot more about what was going on and I was willing to grind thru tedium. I had a lot of fun playing w/ double-hires graphics, digitizing audio via the cassette interface, and doing some rudimentary software cracking. It was a fun time.